


Mutually Assured Destruction

by usuallysunny



Category: It's Always Sunny in Philadelphia
Genre: Angst and Hurt/Comfort, Episode: s09e01 The Gang Broke Dee, Explicit Sexual Content, F/M, Sibling Incest, Smut, Twincest, im sorry
Language: English
Status: Completed
Published: 2019-03-11
Updated: 2019-03-11
Packaged: 2019-11-15 17:48:59
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,486
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/18078113
Author URL: https://archiveofourown.org/users/usuallysunny/pseuds/usuallysunny
Summary: They're trying to break Dee, but they break Dennis too. That's how it is with twins.





	Mutually Assured Destruction

**Author's Note:**

> WARNING: Explicit twincest guys. Don't say I didn't warn ya. I'm sorry, I was always gonna write this trash eventually. Set directly after S9 The Gang Broke Dee.

Dennis slams the front door shut, so hard it rattles in its frame.

Dee opens her mouth to shout at him, to tell him not to slam her shit, but the words die in her throat at the manic look in his eye.

"Dennis…" she's saying his name before she even realises it, but it doesn't calm him down. It makes it worse.

"Those  _bastards…_ " he's sneering through gritted teeth, pacing wildly. His hands fly to his hair and Dee grimaces, feeling pangs of sympathy for the way he punishes his poor curls, " _I_ _diots! Savages!_ I'm going to  _kill_ them."

"Den," she repeats his name and her hand kind of reaches out for him before she pulls it back. The atmosphere blisters awkwardly and she doesn't know what to do, what to say.

After-all, he's still Dennis and she's still Dee. She'll never really understand him… never really love him the way a sister should. She doesn't feel guilty about that. Christ, if anyone is less capable of love than her, it's Dennis. At least they've always had that in common.

"I mean it, Deandra!" he's snarling, her full name alerting her to the fact that he means business, "They  _humiliated_  me. Those goddamn idiots, trying to fool  _me!_  I won't have it, Dee. I won't!"

She figures now isn't the best time to point out the Gang didn't just  _try_ to fool him – they fucked them both over, wholly and without a shred of remorse.

Her blood starts to boil, anger thrumming hot beneath her skin. She can't believe his audacity. How dare he stand there, like  _he's_ the one whose dreams have just been ripped cruelly away, slipping through his fingers as he desperately tried to cling on? God, he's always doing this. He's always taking her shit for himself, always controlling her.

"What the shit are you talking about?" she verbalises the thought, her voice hard, "this isn't about you, Dennis. Goddamn, you are the most selfish son of a bitch I've ever met."

He whips around, blue eyes shining bright and manic.

"Not about me?" he repeats like it's the most ridiculous thing she's ever said, " _not_ about me? Sweet Dee, let's get one thing straight.  _Everything_ in your life should be about me."

Dee gapes at him, shock and grief and a hundred other emotions she can't even begin to decipher rushing through her veins.

"Get out," she whispers finally. Her eyes burn and her throat hurts and she stubbornly blinks back hot tears. "Goddamn it, just get the fuck out."

Something passes over Dennis' face then, something dark and sinister. Dee forces herself not to recoil. She knows that look – like the lights are on but no-one's home, something devastating.

"I don't think so, sis. You owe me an explanation too."

Dee sighs, walking over to her fridge to grab another beer. She's already drunk as shit, but she needs to be even more so if he's insisting on staying.

"I don't owe you shit."

Dennis' temper flares again. "I poured my goddamn heart out to you by that plane, you bitch."

Dee's temper flares too because they're twins and too similar for their own good.

"And you didn't mean a word of it! I'm not stupid. You don't give a shit about me, Dennis. You don't give a shit about anyone."

Something flickers across his face, a glimpse of something real, but it's gone before Dee can fully decipher it.

"I thought you were gonna go and—"  _leave me behind,_ he seems to say but his tongue trips over the words, "You'd make it and I'd be…"  _alone,_ "…stuck with Mac and Charlie and fucking Frank. And you don't deserve it because you're a bitch and a bird and  _goddamn it,_ Dee, will you get me a goddamn beer?!"

Dee's staring at him, stunned at his outburst, and her eyes are so wide she probably looks more like a fish than a bird.

"What happened to you, Dennis?" She asks quietly, more to herself than to him.

She doesn't recognise the person standing in-front of her, his frenzied eyes flashing with betrayal and so much hatred. What happened to the little boy who made her laugh, who snuck food under her door when their Mom gave him dinner but not her? They used to be close, joint at the hip and able to communicate in a language no-one else could hear. He used to climb into her crib at night and touch his fingertips to hers, just needing to be near her, and somewhere along the way they got lost.

Like an addict desperate for her next fix, she's always craved his attention. She remembers the night she lost her virginity, to  _Mac_ of all people. He'd drunkenly snuck in the wrong window, looking for Dennis but still smelling like his prom date. It was great. Her makeup was smudged from crying all night and he refused to kiss her and her back brace got in the way, but it was  _fine._

She's never told anyone that. Her whole life, she's pretended it was this big deal, some sordid secret she kept from her twin.

Really, Dennis never asked.

She misses him. In this sick, manic way, she misses him. He's standing right in-front of her and she misses him so bad, it makes her chest hurt.

His eyes flash angrily and he pushes past her, muttering under his breath and grabbing the beer himself. Her own lies forgotten on the table; her stomach is churning enough.

"My  _sister_ betrayed me, that's what."

"I didn't betray you, you asshole. You thought I was making something of myself. You just couldn't bear the thought of me becoming a success when you were still such a fucking loser. That's your problem, Dennis. Your own jealousy, your ridiculous need to control everything. It's  _always_ been your problem. So I'm not going to apologise for what I did. I wanted success and happiness and you've  _always_  denied me both. Yeah, I hate Mac and I hate Charlie for what they did, but they're fucking  _saints_ compared to you. I wanted  _rid_  of you and given the chance, I'd do it again."

Dennis' eyes flash with pure, unadulterated fury and for a moment, Dee's actually scared of him.

He lunges for her, stopping in his tracks when they're toe to toe. His top lip curls into a snarl and his hands twitch, like he's itching to choke the life out of her.

Her breath hitches, her hands flying to the kitchen table behind her.

His eyes, a darker shade of scorching blue, flicker from her eyes to her mouth and his hands cover hers on the table, caging her in. There's nowhere to run and Dee hopes he can't hear her heart, pounding against her ribcage.

"Let me say this very slowly, in a way even  _you_ can understand…" he starts, his voice low and deep and sinister, "…you are pathetic and a bitch and  _nothing_ without me. You will always croak; you will always fail. You're also alone. You should've let me help you pick a suitable partner, sis."

Dee's eyes narrow, her blood turned to ice.

"I don't need your help, boner. I have a new man in my bed every week."

"But do they stay?" Dennis reaches out, grabbing a stray strand of blonde hair and twirling it around his finger, "You're not exactly lucky when it comes to men, Sweet Dee. They come and go for you, but  _I'm_  the constant. I'm always here."

He says it like it's positive, like not being able to tell where he ends and she begins is a good thing. She hates him, her cold and cruel brother, looming over her like a dark shadow, a bad dream… always in the corner of her vision, like when eyelashes stick together.

"I hate you," she says because she does and it's all she can think to say.

His lip curls and his brow arches.

"The feeling's mutual, sweetheart."

The atmosphere blisters, heady and intense, as they stare at each other.

Dee feels like she's standing on the edge of a precipice and she doesn't know why – like the ground is going to shake and moan and open up at any minute.

Tomorrow, she won't remember who moved first.

All she will remember is the gap between them closing, their mouths crashing together with one joint, heated moan.

Her knees buckle and his hands fly to her waist, pulling her flush against him. Her mind floods and she can't make sense of what's happening, but she opens her mouth for him regardless, a sick lust snapping at her heels when his tongue tangles with hers.

 _This is so fucked up,_ she thinks as his mouth slants desperately over hers. It's her  _brother_ and her  _twin_ and Jesus Christ, his erection is pressing between her thighs and she can feel wetness between them. It's so fucked up but maybe that's okay because  _she's_ fucked up too – and Dennis has played a huge part in that. She doesn't care, because she's broken and tired and the joke's always on Dee. 

"Oh my god," she mutters under her breath, tipping her head back as he breaks away from her neck and plants hot kisses down the length of her flushed skin.

"Shut up," he demands huskily, probably irritated by the mention of a god unless it's him. She's all too aware of his ridiculous god-complex and maybe she'll have to buy into it, because if she wasn't headed for hell before, she sure as shit is now.

Maybe he's all that's left.

He's grabbing at her thighs, bunching her dress – she was planning on being a dress girl when she was famous – around her waist. He hooks his hands under her thighs, smoothly lifting her, and her pumps fly off and across the room. The _bang_ as they hit the wall pierces the silence and suddenly her chest hurts.

He doesn't give her any time to overthink whatever the hell this is, because he's fast, his movements laced with anger and a passion that's bursting through the surface. He's fast because he hates himself; she's fast for the same reason.

He perches her on the edge of the kitchen table and roughly shoves her panties to the side. Then he's touching her – her  _brother_ is touching her  _there_ – and Dee's not gagging. Two fingers spread her wetness, before he plunges them inside.

"Fuck," she bites out, long legs wrapping around his waist and nails digging into his shoulders.

His eyes connect with hers then, blue on blue, so similar it makes her sick. It's not something exciting, but something paralysing, like when all the air is sucked up around you and it feels like you've been punched in the stomach.

It's silent save for their heavy breathing and Dee's eyes burn when he removes his fingers. They glisten with her juices as he undoes his belt and she feels a blush rise to her cheeks.  _So fucked up, so fucked up,_ she reminds herself, over and over again, but makes no attempt to stop.

Before she knows it, he's pulling a condom out his back pocket – because this doesn't need to be even more fucked up than it already is – and slipping it on his erect cock and Dee can't bring herself to look.

Then he's tugging her closer, her ass perched on the edge of the table, and he's whispering filth in her ear.  _My good girl,_ he says.  _You're gonna take it all,_ he says.  _Gonna make you come so hard,_ he says.

It's obscene, disgusting really, and her eyes burn with tears when he finally pushes inside her. He pauses for a moment, buried to the hilt, and the world seems to still as they stare at each other. There's no going back now. 

They're all fucked up - them, Mac, Charlie and Frank. But of all the gross, terrible things they've done over the years, this has got to be the worst and  _of course_ it's the two of them responsible for it.

Because they  _are_ the worst.

They probably have around three redeeming qualities between them and it's not surprising they fit together so well like this. Who else could handle them? Could look at them and see anything other than shared histories of greed and neglect and cruelty?

Dee holds on to him as he starts to move inside her and how sick is it, how fucked up, that it feels so good? It's like every part of her has  _always_ had his name carved on it, made to fit and surround him just like this. Two pieces of the same puzzle.

His hips start to move and pound harder as he fucks her into the kitchen table and she thinks it's unfair, how he's as good at this as he's always said he is.

The table moans and creaks, the sound joining their pants and heavy breathing, as Dee comes first for the first time since she  _can't remember when_. White hot pleasure rushes through her, sparking from the tip of her toes and eclipsing anything she ever  _thought_ was pleasure in the past.

Dennis buries his face in her hair when he comes. The sick freak barely makes a sound, quiet in a way that borders on sinister, always in control.

It's only when he pulls out of her, leaving her wincing and aching and already empty, that Dee realises what she's done.

She swallows the bitterness that rises as bile from the back of her throat, watching him through blurred vision as he pulls his pants up and buckles his belt. It's quiet, but not uncomfortably so. There was a time when they shared everything, two misfits who didn't have anyone else. The Gang tried to break Dee today, but ended up breaking him too. Despaired, Dee thinks that's just the way it is with twins. She'll always be tied to him, never able to break the thread. 

Together since the womb, she's loved him every day of her life - and even before. It's not conventional, none of them are conventional, but if she could feel things, she would feel them for Dennis. And if he could love anyone, she's sure he would love her (and maybe Mac, but that's another tangled web she's not getting caught up in).

She readjusts her dress and Dennis takes a step back. Running a hand through his now-ruined curls, he has the sense to look at least a little sheepish. A little less brazen, less obscene.

He clears his throat and delivers the Gang's infamous party line.

"You wanna just... move past this?"

Dee nods, numb. Everything's different, yet nothing's changed.

Tomorrow, when he puts his hands on her waist to move her out of his way, she'll force herself not to flinch.


End file.
